Definition of QWERTY - denoting the standard layout on English-language typewriters and keyboards, having q, w, e, r, t, and y as the first keys from the Definition of QWERTY - denoting the standard layout on English-language typewriters and keyboards, having q, w, e, r, t, and y as the first keys from the
DNA molecules have a consistant width of about 2.5 nanometers (a nanometer is one billionth of a meter; human hair has a thickness of roughly 20,000 nm to 180,000 nm), but the length of DNA molecules varies greatly. Scientists usually describe the length of DNA using a unit called kb or kbp. One kb is 1000 base pairs, the base pair being the basic repeating nucleotide unit of the DNA chain. Each base pair has a length of 0.33 nm. Plasmid DNA might have a length of 1-200 kb, or 0.33 nm to 66 nm. Bacterial chromosomal DNA length would be perhaps 3800 kb, or 1300 nm (1.3 microns).
Probe size is important because longer probes hybridize less specifically than shorter probes, a short strand of DNA or RNA (often 10â25 nucleotides) which is complementary to a given target sequence, it can be used to identify or locate the target.. The overlap defines the resolution of detectable features.